Improve LA rail transit, SD trolley lines, and connect the two systems. Lots of people drive between LA and SD, and would gladly switch to a train if it were just as fast/not too expensive. Amtrak exists, but it's slow, has a limited capacity, and costs too much. We need a true commuter line.

They could really improve travel time between LA and SD by double tracking the entire line. I know there are a few spots that wouldn't work (due to ROW or physical limitations) but there are still plenty of places where they could add a second track and limit the number of times a train would have to stop and wait for another train.

Long term, they can work on things like grade separation, triple tracking where applicable, and eventually tunneling to bypass places they can't add capacity (Del Mar, for example).